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ARM Linux

Mobile WiFi NAS on Raspberry Pi with TrueCrypt

In ARM Linux, General Linux on 1 June 2014 with no comments 645 views

Mobile NAS sounds like an idea worth waiting for to run on my mini Raspberry Pi Model A. Unfortunately, it only took me a while, before abandoning it. I’ve waited since writing about Raspberry Pi USB problem, that is to finally cut the backfeeding power line from the el cheapo powered USB hub. There comes [...]

Any m-by-n Matrix Keypad for Raspberry Pi

In ARM Linux, Coding on 9 February 2014 with no comments 424 views

What about instantiating any m x n matrix keypad by a Python class? Raspberry Pi takes me to learn how to build a Python class for the first time while expanding my initial WiringPi-based matrix keypad into a derivative work. A matrix keypad instance is defined by: Actual GPIO pins used forming the row and [...]

Duplicate/Restore ARM Linux Image to MMC/SD Card (BeagleBoard and DevKit ARM)

In ARM Linux on 25 March 2013 with no comments 2094 views

By booting from MMC/SD card, you can bring up your BeagleBoard-xM or DevKit8500D (both are ARMv7). It is the only way for the xM (microSD card to be exact), while with DevKit, you have the option to flash it to the board for NAND-boot once you’re sure that it works with SD card. eLinux wiki [...]

Modem usb_modeswitch in Raspberry Pi

In ARM Linux on 25 March 2013 with 2 comments 6106 views

USB modem these days are plug-and-play as CD-ROM first allowing driver and internet dialer application installations and then as modem afterwards. This Windows-behavior is handled by USB_ModeSwitch in Linux. Likely three years ago we did eject and other driver attachment by writing udev rules. Now it’s almost automatically attached as modem after insertion and people [...]

Raspberry Pi Common USB Problems

In ARM Linux on 24 March 2013 with 1 comment 6537 views

USB problem is the first thing to arise with Raspberry Pi when plugging-in peripherals. This isn’t exclusive though, learning that my Linux laptop also has it and the higher ARM architecture, BeagleBoard-xM, also experiences the same issue sometime. But with Raspberry Pi (RPi) in

Raspberry Pi: Membrane (Matrix) Keypad as GPIO Input

In ARM Linux on 13 March 2013 with Comments Off 4549 views

Membrane matrix keypad using GPIO as Raspberry Pi input has been my goal since WiringPi deployed in the first place. To begin with, GPIO hacking was initially started with some important basics (see previous post). Without external system (other interfacing chip), the 3×4 membrane keypad reserved all seven GPIO pins plus one pin used for [...]

Raspberry Pi GPIO Input Button Basics

In ARM Linux on 11 March 2013 with no comments 2654 views

When you start hacking Raspberry Pi’s GPIO, first thing to keep in mind is the +3.3V CMOS logic level voltage despite the 5V supply. Secondly, read references about current limiting resistors (eLinux Wiki has a section there). What to avoid then? Try not to physically short the GPIO pin to ground when it is programmed [...]

Cross-Compiling for Ubuntu ARM by ffmpeg Example

In ARM Linux, Ubuntu on 5 November 2012 with 8 comments 7702 views

This has been a delayed post since I only figure out how to solve configure error just now. It wasn’t really necessary to cross-compile last year because compiling ffmpeg directly on the ARM-board finished overnight (despite the low CPU). Anyway, in this post I’m still using the board to easily retrieve package dependencies from Ubuntu [...]

Simple ffmpeg UDP Video Streaming (from BeagleBoard running Ubuntu)

In ARM Linux, Ubuntu on 5 November 2012 with no comments 16284 views

I really mean simple, this is a one command line UDP stream from the BeagleBoard (running Ubuntu ARM) to my desktop (IP address 192.168.1.19 in this example), the source video is an FLV file inside the ARM-board: $ ffmpeg -i UNIQLO_MIXPLAY.flv -v 0 -vcodec mpeg4 -f mpegts udp:192.168.1.19:1234 Although it’s a break-dance video, it plays [...]

Zabbix Proxy: distributed NMS monitoring via embedded Linux (Ubuntu on BeagleBoard)

In ARM Linux on 19 July 2012 with no comments 653 views

As already mentioned in previous post’s introduction, proof of concept on how Zabbix Proxy works under unreliable communication is what this next post about. The idea is to have these scenarios tested: independent SNMP data polling by individual NMS proxy (embedded system) intermittent connection between main/master NMS server with its proxy Of course we’ll do [...]